Tool post



K. H. cUMRlNE March 2o, 1928.1 A 1,662,959

Toon ros Filed Aug. 20. 192e 2 Sheets-Sheet 1 March 20, 1928.

Y K. H. cRuMRlNE TooL'PosT l Filed Aug. 20. 1926 l2 Sheets-Sheet 2 'l 57 29 30 I ,Q s 254 13 27/ 77 y 2 ze@ j@ 267 26 Z5 1, J5

um Ml .Patented Mar. 20, 192.8.l

UNITED STATES i 1,662,959 PATENT." OFFICE.' I

KENNEDY H. CBUMRINE, OF OLEVELAND, OHIO, 'ASSIGNOB TO GISHOLT MACHINE COMPANY, OF MADISON, WISCONSIN, A CORPORATION OF ILLINOIS.`

moor. roar.

application mea'augm 2o, Iwas. serial 1ra-Isaacs.

This invention relates to tool posts for lathes and other machine tools employing tool posts, and has reference more particularly to' tool posts of the turret type capable of holding a plurality of tools and ofV being indexed to bring the tools successively into operative relation to the work.

The main object of the present invention is to provide a very simple, inexpensive and efficient tool post, in which', by swlnging 'a handle lever through yan angle4 slightly greater than the indexin angle, the tool post will be indexedand c amped. Another object is to provide an improved and simplified mechanism for unlocklng thetool` holder when the latter is to beindexed.

-In the accompanying drawin I have illustrated the invention as em odied in a square turret tool post designed to be indexed through an angle of ninety degrees,

but it will be understood, of course, that the invention isA equally applicable to tool posts designed to be indexed through greater or less angles.

Referring to the drawings- Fig. 1 is atop plan view;

Fig. 2 is a vertical section taken on the` line 2--2 of Fig. 1;

Fig. 3 is a vertical section taken onthe line 3-3 of Figli Fig. 4 is a sectional detail through the pivot of the lock releasing pawl and its aej tuat-ing spring; and

Fig. 5 is a perspective view of the lock releasing pawl. A

Referring to the drawings, ldesignates the base 'of the tool post that is held down on the cross-slide by bolts- 11 and nuts 12 which latter are adjustable in the usual T'- slots of the cross-slide (not shown).` The p upper portion 10 of the base 10 is circular,

and mounted thereon is the tool holder body 13 equipped with the' usual lateral lian e 13 carrying screws'14 by which the toos are clamped on the wedges 15.. Extending coaxially through the base 10 and body 13 'is astud 16 formed with an annular shoulder 17 and equipped on its lower threaded end with a nut 18. by which the body 13 is held down on the base 10. The body is further centered and revolubly guided on the .base

v by a circular flange 19 on its lower end embracing th'e circular upper portion 1.0 Aof the base.

a thrust spring '22 footed on a cap 23 that closes the lower end of the bushing 20. The bottom of the body 13 is formed with a plurality of spaced sockets, corresponding in number to the dierent positions to which the post is designed to be indexed, said sockets preferably including internall t-aperedtightly fitting hardened steel ush# ings 24 to receive the corres ondingly tapered upperv end of the loc in bolt 21.r

ertically slidable in the tool older 13 abovev the socket bushings 24 are plungers 25. The lower ends f these plungers extend through holes in the sockets 24, while their upper ends extend some distance above the top of the tool holder 13. The plungers are normally upheld to permit the locking bolt to enter the sockets by thrust springs 26 footed on'the tops' of the bushings 24l and attheir upper ends abuttingagainst collars n 27 on the plunvers; the springs 26 being -housed in chambers.,28 formed in the tool circumferential' groovev or channel 33; andv within said channel is pivote'd on a vertical pivot stud 34 (Fig. 4) one end of a curved a screw 32. The hub 30 is formed witha p awl 35. Thisv pawl, shown in `isolated dev ltail in Fig. .5, has formed on its bottom a sloping cam 36 extending from its forward free end' rearwardly to a transverse shoulder 37 located at the base of the cam. (.)ntheg outer side of the ,central deep portion "off the pawl there is also formed a` cam incline 3.8. A semi-circular wire spring centrall 4anchored on a stud 39 (Fig. 4) has one lim 40 thereof footed against a p1n 41 (Fig. 1) i depending from the top wall of the channel 33, while its otherlimb '42 is in thrust engagement with the inner side of the pawl 35,v forcing the latter outwardly againstl a guard ring 43 which covers the open side of the channel` 33. With vthe pawl thul n' Q ,Lasarte swing of the handle 31 counterclockwise f orv the length of thel cam 36 (which in practice is about thirty degrees) causes said cam to depress the plunger which overlies the locking bolt 21, thereby depressing the latter to release position. At this instant the shoulder 37 comes into side contact withthe upper end of thel plunger, and through vthe thrust on the latter the tool holder 13 is indexed to the next position (ninety degrees in the instance shown), whereupon the` ooking bolt 21 snaps into locking engagement with the next tool holder socket. It may here be noted that when'the locking bolt is depressed to release position the plane of contact of the plunger and locklng bolt co insides with the plane of contact of the tool holder and base, and the locking bolt is held depressed by the plunger until its upper end engages with the under side of the ltool ho der, the lower end of the plunger, as the tool holder is indexed, sliding over the top surface ofl the base. On the return swing of the handle, the cam 38engages theside of the upper end of the next plunger and the pawl is swung inwardly thereby, against the thrust of the sprin passessaid plunger; whereupon the spring 42 returns the pawl to a position wherein its forward end overlies the top of said'plunger, as shown in Fig. 3.

' This return movement of the handle lever in a clockwise direction causes the hub to screw down slightly on the post 29, thus clamping or binding the 'parts of the toolA post together and maintaining the entire post rlgid.

- From the foregoingit-will be seen Vthat the locking, indexing,` relooking and clamping.

operatlons are performed by the single forward and reverse movements of the handle lever throu h an arc. of approximately one hundred an I claimtwenty degrees.l 1. In a tool post, the combination of a base, an upwardly spring-pressed locking bolt'in said base, va tool holder rotatable on said base having sockets in its under side to interlock with the'upper end of-said bolt, a fixed stud extending centrally through said base and tool holder and formed with a post v 42, until the pawlon its upper end, upwardly spring-pressed plungers in said tool holder axially aligned with said sockets and adapted, when depressed, toA force said bolt to unlocking position, said plungers extending above said tool holder, an operating lever having a hub ro- .tatable on said post, and a pawl pivoted on said hub and formed with a cam operating, when the hub is turned, to depress a plunger, and with a shoulder operatind, throughr side vcontact with the upper end o the depressed plunger, to index said tool holderto anew.

position.

2. In a tool post, the ,combination of a base, .an upwardly spring-ressed lockingA bolt in said base, a tool' hol er rotatable on said-base havin socket in its under side to interlock with t e 'upper end of said bolt,a fixed stud extending centrally through said base andv tool holder and formed with a screwthreaded post on its upper end, upwardly spring-pressed plungers in said tool holder axially aligned with said sockets and adapted, when depressed, to` force said bolt to unlocking position, said plungers extending above said tool holder, an o erating lever havlng an internally threaded ub rotatable on said threaded post, said hub formed with a circumferential channel, and a pawl vertically pivoted on said hubin said channel and formed on its -bottom with. a cam operating,

when the hub is turned, to depress a plunger,

and with a shoulder at the base of said cam operating, through side lcontact with the upi per` end of the depressed plunger, to index vsaid tool holder to a new position.

3. In 'a tool post, thecombinaton of a base, 1an upwardly spring-pressed locking bolt in said base, a tool holder rotatable on said base havin sockets in its .underside to interlock with t e upper end of said bolt', a fixed stud extending centrally through said base and toolholder formed with a threaded post` on its upper end, upwardly springpressed plungers in said tool holder` axially' aligned with saidsockets and adapted, when depressed, to force said bolt to unlocking position, said plungers textending above said tool holder, an operating lever having an internally threaded hub rotatable on said threaded post, a pawl pivoted on said hub and formed on its bottom withaacam operating, when thehub is turned, to depress a plunger, a shoulder at the base of said cam operating, through side contact with the upper end' of the depressed plunger, to index said tool holder, 'and with a cam'on its outer sidefor swinging said pawl inwardly past the next plunger on the return swing of said lever, and a spring opposing the inward swing of said pawl.

KENNEDY H. CRUMRINE. 

